8 #include <threads_int.h>
15 #include <arch_config.h>
19 #define DEBUG_TRACE_SWITCH 0
20 #define BREAK_ON_SWITCH 0 // Break into bochs debugger on a task switch
28 Uint8 State; // 0: Unavaliable, 1: Idle, 2: Active
36 extern void APStartup(void); // 16-bit AP startup code
38 extern Uint GetRIP(void); // start.asm
39 extern Uint SaveState(Uint *RSP, Uint *Regs);
40 extern void NewTaskHeader(void); // Actually takes cdecl args
42 extern Uint64 gInitialPML4[512]; // start.asm
43 extern tShortSpinlock glThreadListLock;
46 extern int giTotalTickets;
47 extern int giNumActiveThreads;
48 extern tThread gThreadZero;
49 extern void Threads_Dump(void);
50 extern void Proc_ReturnToUser(void);
51 extern void Time_UpdateTimestamp(void);
54 //void ArchThreads_Init(void);
56 void MP_StartAP(int CPU);
57 void MP_SendIPI(Uint8 APICID, int Vector, int DeliveryMode);
59 void Proc_IdleTask(void *unused);
60 //void Proc_Start(void);
61 //tThread *Proc_GetCurThread(void);
62 int Proc_NewKThread(void (*Fcn)(void*), void *Data);
63 // int Proc_Clone(Uint *Err, Uint Flags);
64 // int Proc_SpawnWorker(void);
65 Uint Proc_MakeUserStack(void);
66 //void Proc_StartUser(Uint Entrypoint, Uint *Bases, int ArgC, char **ArgV, char **EnvP, int DataSize);
67 void Proc_StartProcess(Uint16 SS, Uint Stack, Uint Flags, Uint16 CS, Uint IP) NORETURN;
68 int Proc_Demote(Uint *Err, int Dest, tRegs *Regs);
69 //void Proc_CallFaultHandler(tThread *Thread);
70 //void Proc_DumpThreadCPUState(tThread *Thread);
71 void Proc_Scheduler(int CPU, Uint RSP, Uint RIP);
74 //!\brief Used by desctab.asm in SyscallStub
75 const int ci_offsetof_tThread_KernelStack = offsetof(tThread, KernelStack);
76 // --- Multiprocessing ---
78 volatile int giNumInitingCPUs = 0;
79 tMPInfo *gMPFloatPtr = NULL;
80 tAPIC *gpMP_LocalAPIC = NULL;
81 Uint8 gaAPIC_to_CPU[256] = {0};
83 tCPU gaCPUs[MAX_CPUS];
86 // --- Error Recovery ---
87 Uint32 gaDoubleFaultStack[1024];
91 * \fn void ArchThreads_Init(void)
92 * \brief Starts the process scheduler
94 void ArchThreads_Init(void)
101 // Mark BSP as active
104 // -- Initialise Multiprocessing
105 // Find MP Floating Table
106 // - EBDA/Last 1Kib (640KiB)
107 for(pos = KERNEL_BASE|0x9F000; pos < (KERNEL_BASE|0xA0000); pos += 16) {
108 if( *(Uint*)(pos) == MPPTR_IDENT ) {
109 Log("Possible %p", pos);
110 if( ByteSum((void*)pos, sizeof(tMPInfo)) != 0 ) continue;
111 gMPFloatPtr = (void*)pos;
115 // - Last KiB (512KiB base mem)
117 for(pos = KERNEL_BASE|0x7F000; pos < (KERNEL_BASE|0x80000); pos += 16) {
118 if( *(Uint*)(pos) == MPPTR_IDENT ) {
119 Log("Possible %p", pos);
120 if( ByteSum((void*)pos, sizeof(tMPInfo)) != 0 ) continue;
121 gMPFloatPtr = (void*)pos;
128 for(pos = KERNEL_BASE|0xE0000; pos < (KERNEL_BASE|0x100000); pos += 16) {
129 if( *(Uint*)(pos) == MPPTR_IDENT ) {
130 Log("Possible %p", pos);
131 if( ByteSum((void*)pos, sizeof(tMPInfo)) != 0 ) continue;
132 gMPFloatPtr = (void*)pos;
138 // If the MP Table Exists, parse it
143 Log("gMPFloatPtr = %p", gMPFloatPtr);
144 Log("*gMPFloatPtr = {");
145 Log("\t.Sig = 0x%08x", gMPFloatPtr->Sig);
146 Log("\t.MPConfig = 0x%08x", gMPFloatPtr->MPConfig);
147 Log("\t.Length = 0x%02x", gMPFloatPtr->Length);
148 Log("\t.Version = 0x%02x", gMPFloatPtr->Version);
149 Log("\t.Checksum = 0x%02x", gMPFloatPtr->Checksum);
150 Log("\t.Features = [0x%02x,0x%02x,0x%02x,0x%02x,0x%02x]",
151 gMPFloatPtr->Features[0], gMPFloatPtr->Features[1],
152 gMPFloatPtr->Features[2], gMPFloatPtr->Features[3],
153 gMPFloatPtr->Features[4]
157 mptable = (void*)( KERNEL_BASE|gMPFloatPtr->MPConfig );
158 Log("mptable = %p", mptable);
160 Log("\t.Sig = 0x%08x", mptable->Sig);
161 Log("\t.BaseTableLength = 0x%04x", mptable->BaseTableLength);
162 Log("\t.SpecRev = 0x%02x", mptable->SpecRev);
163 Log("\t.Checksum = 0x%02x", mptable->Checksum);
164 Log("\t.OEMID = '%8c'", mptable->OemID);
165 Log("\t.ProductID = '%8c'", mptable->ProductID);
166 Log("\t.OEMTablePtr = %p'", mptable->OEMTablePtr);
167 Log("\t.OEMTableSize = 0x%04x", mptable->OEMTableSize);
168 Log("\t.EntryCount = 0x%04x", mptable->EntryCount);
169 Log("\t.LocalAPICMemMap = 0x%08x", mptable->LocalAPICMemMap);
170 Log("\t.ExtendedTableLen = 0x%04x", mptable->ExtendedTableLen);
171 Log("\t.ExtendedTableChecksum = 0x%02x", mptable->ExtendedTableChecksum);
174 gpMP_LocalAPIC = (void*)MM_MapHWPage(mptable->LocalAPICMemMap, 1);
176 ents = mptable->Entries;
179 for( i = 0; i < mptable->EntryCount; i ++ )
186 Log("%i: Processor", i);
187 Log("\t.APICID = %i", ents->Proc.APICID);
188 Log("\t.APICVer = 0x%02x", ents->Proc.APICVer);
189 Log("\t.CPUFlags = 0x%02x", ents->Proc.CPUFlags);
190 Log("\t.CPUSignature = 0x%08x", ents->Proc.CPUSignature);
191 Log("\t.FeatureFlags = 0x%08x", ents->Proc.FeatureFlags);
194 if( !(ents->Proc.CPUFlags & 1) ) {
199 // Check if there is too many processors
200 if(giNumCPUs >= MAX_CPUS) {
201 giNumCPUs ++; // If `giNumCPUs` > MAX_CPUS later, it will be clipped
205 // Initialise CPU Info
206 gaAPIC_to_CPU[ents->Proc.APICID] = giNumCPUs;
207 gaCPUs[giNumCPUs].APICID = ents->Proc.APICID;
208 gaCPUs[giNumCPUs].State = 0;
212 if( !(ents->Proc.CPUFlags & 2) )
214 MP_StartAP( giNumCPUs-1 );
221 Log("\t.ID = %i", ents->Bus.ID);
222 Log("\t.TypeString = '%6c'", ents->Bus.TypeString);
226 Log("%i: I/O APIC", i);
227 Log("\t.ID = %i", ents->IOAPIC.ID);
228 Log("\t.Version = 0x%02x", ents->IOAPIC.Version);
229 Log("\t.Flags = 0x%02x", ents->IOAPIC.Flags);
230 Log("\t.Addr = 0x%08x", ents->IOAPIC.Addr);
232 case 3: // I/O Interrupt Assignment
234 Log("%i: I/O Interrupt Assignment", i);
235 Log("\t.IntType = %i", ents->IOInt.IntType);
236 Log("\t.Flags = 0x%04x", ents->IOInt.Flags);
237 Log("\t.SourceBusID = 0x%02x", ents->IOInt.SourceBusID);
238 Log("\t.SourceBusIRQ = 0x%02x", ents->IOInt.SourceBusIRQ);
239 Log("\t.DestAPICID = 0x%02x", ents->IOInt.DestAPICID);
240 Log("\t.DestAPICIRQ = 0x%02x", ents->IOInt.DestAPICIRQ);
242 case 4: // Local Interrupt Assignment
244 Log("%i: Local Interrupt Assignment", i);
245 Log("\t.IntType = %i", ents->LocalInt.IntType);
246 Log("\t.Flags = 0x%04x", ents->LocalInt.Flags);
247 Log("\t.SourceBusID = 0x%02x", ents->LocalInt.SourceBusID);
248 Log("\t.SourceBusIRQ = 0x%02x", ents->LocalInt.SourceBusIRQ);
249 Log("\t.DestLocalAPICID = 0x%02x", ents->LocalInt.DestLocalAPICID);
250 Log("\t.DestLocalAPICIRQ = 0x%02x", ents->LocalInt.DestLocalAPICIRQ);
253 Log("%i: Unknown (%i)", i, ents->Type);
256 ents = (void*)( (Uint)ents + entSize );
259 if( giNumCPUs > MAX_CPUS ) {
260 Warning("Too many CPUs detected (%i), only using %i of them", giNumCPUs, MAX_CPUS);
261 giNumCPUs = MAX_CPUS;
264 while( giNumInitingCPUs )
265 MM_FinishVirtualInit();
267 Panic("Uh oh... MP Table Parsing is unimplemented\n");
270 Log("No MP Table was found, assuming uniprocessor\n");
277 MM_FinishVirtualInit();
281 // Initialise Normal TSS(s)
282 for(pos=0;pos<giNumCPUs;pos++)
287 gTSSs[pos].RSP0 = 0; // Set properly by scheduler
288 gGDT[7+pos*2].LimitLow = sizeof(tTSS) & 0xFFFF;
289 gGDT[7+pos*2].BaseLow = ((Uint)(&gTSSs[pos])) & 0xFFFF;
290 gGDT[7+pos*2].BaseMid = ((Uint)(&gTSSs[pos])) >> 16;
291 gGDT[7+pos*2].BaseHi = ((Uint)(&gTSSs[pos])) >> 24;
292 gGDT[7+pos*2+1].DWord[0] = ((Uint)(&gTSSs[pos])) >> 32;
295 for(pos=0;pos<giNumCPUs;pos++) {
296 __asm__ __volatile__ ("ltr %%ax"::"a"(0x38+pos*16));
299 __asm__ __volatile__ ("ltr %%ax"::"a"(0x38));
302 // Set Debug registers
303 __asm__ __volatile__ ("mov %0, %%db0" : : "r"(&gThreadZero));
304 __asm__ __volatile__ ("mov %%rax, %%db1" : : "a"(0));
306 gaCPUs[0].Current = &gThreadZero;
308 gThreadZero.MemState.CR3 = (Uint)gInitialPML4 - KERNEL_BASE;
309 gThreadZero.CurCPU = 0;
310 gThreadZero.KernelStack = 0xFFFFA00000000000 + KERNEL_STACK_SIZE;
312 // Set timer frequency
313 outb(0x43, 0x34); // Set Channel 0, Low/High, Rate Generator
314 outb(0x40, PIT_TIMER_DIVISOR&0xFF); // Low Byte of Divisor
315 outb(0x40, (PIT_TIMER_DIVISOR>>8)&0xFF); // High Byte
317 // Create Per-Process Data Block
318 if( !MM_Allocate(MM_PPD_CFG) )
320 Warning("Oh, hell, Unable to allocate PPD for Thread#0");
323 Log_Log("Proc", "Multithreading initialised");
327 void MP_StartAP(int CPU)
329 Log("Starting AP %i (APIC %i)", CPU, gaCPUs[CPU].APICID);
330 // Set location of AP startup code and mark for a warm restart
331 *(Uint16*)(KERNEL_BASE|0x467) = (Uint)&APStartup - (KERNEL_BASE|0xFFFF0);
332 *(Uint16*)(KERNEL_BASE|0x469) = 0xFFFF;
333 outb(0x70, 0x0F); outb(0x71, 0x0A); // Warm Reset
334 MP_SendIPI(gaCPUs[CPU].APICID, 0, 5);
338 void MP_SendIPI(Uint8 APICID, int Vector, int DeliveryMode)
340 Uint32 addr = (Uint)gpMP_LocalAPIC + 0x300;
344 val = (Uint)APICID << 24;
345 Log("*%p = 0x%08x", addr+0x10, val);
346 *(Uint32*)(addr+0x10) = val;
348 val = ((DeliveryMode & 7) << 8) | (Vector & 0xFF);
349 Log("*%p = 0x%08x", addr, val);
350 *(Uint32*)addr = val;
357 void Proc_IdleTask(void *ptr)
360 cpu->IdleThread = Proc_GetCurThread();
361 cpu->IdleThread->ThreadName = (char*)"Idle Thread";
362 Threads_SetPriority( cpu->IdleThread, -1 ); // Never called randomly
363 cpu->IdleThread->Quantum = 1; // 1 slice quantum
364 for(;;) HALT(); // Just yeilds
368 * \fn void Proc_Start(void)
369 * \brief Start process scheduler
371 void Proc_Start(void)
379 for( i = 0; i < giNumCPUs; i ++ )
382 if(i) gaCPUs[i].Current = NULL;
384 Proc_NewKThread(Proc_IdleTask, &gaCPUs[i]);
387 gaCPUs[i].IdleThread = Threads_GetThread(tid);
391 if( i != giProc_BootProcessorID ) {
396 // BSP still should run the current task
397 gaCPUs[0].Current = &gThreadZero;
399 // Start interrupts and wait for APs to come up
400 Log("Waiting for APs to come up\n");
401 __asm__ __volatile__ ("sti");
402 while( giNumInitingCPUs ) __asm__ __volatile__ ("hlt");
404 Proc_NewKThread(Proc_IdleTask, &gaCPUs[0]);
406 // Start Interrupts (and hence scheduler)
407 __asm__ __volatile__("sti");
409 MM_FinishVirtualInit();
410 Log("Multithreading started");
414 * \fn tThread *Proc_GetCurThread(void)
415 * \brief Gets the current thread
417 tThread *Proc_GetCurThread(void)
420 return gaCPUs[ GetCPUNum() ].Current;
422 return gaCPUs[ 0 ].Current;
426 int Proc_NewKThread(void (*Fcn)(void*), void *Data)
429 tThread *newThread, *cur;
431 cur = Proc_GetCurThread();
432 newThread = Threads_CloneTCB(NULL, 0);
433 if(!newThread) return -1;
436 newThread->MemState.CR3 = cur->MemState.CR3;
439 newThread->KernelStack = MM_NewKStack();
441 if(newThread->KernelStack == 0) {
446 rsp = newThread->KernelStack;
447 *(Uint*)(rsp-=8) = (Uint)Data; // Data (shadowed)
448 *(Uint*)(rsp-=8) = 1; // Number of params
449 *(Uint*)(rsp-=8) = (Uint)Fcn; // Function to call
450 *(Uint*)(rsp-=8) = (Uint)newThread; // Thread ID
452 newThread->SavedState.RSP = rsp;
453 newThread->SavedState.RIP = (Uint)&NewTaskHeader;
454 Log("New (KThread) %p, rsp = %p\n", newThread->SavedState.RIP, newThread->SavedState.RSP);
457 Threads_AddActive(newThread);
459 return newThread->TID;
463 * \fn int Proc_Clone(Uint Flags)
464 * \brief Clone the current process
466 int Proc_Clone(Uint Flags)
468 tThread *newThread, *cur = Proc_GetCurThread();
472 newThread = Threads_CloneTCB(NULL, Flags);
473 if(!newThread) return -1;
475 // Save core machine state
476 rip = SaveState(&newThread->SavedState.RSP, &_savedregs[0]);
478 outb(0x20, 0x20); // ACK Timer and return as child
479 __asm__ __volatile__ ("sti");
483 // Initialise Memory Space (New Addr space or kernel stack)
484 if(Flags & CLONE_VM) {
485 newThread->MemState.CR3 = MM_Clone();
486 newThread->KernelStack = cur->KernelStack;
489 Log_Error("Proc", "Proc_Clone: Don't leave CLONE_VM unset, use Proc_NewKThread instead");
493 Log("New (Clone) %p, rsp = %p\n", rip, newThread->SavedState.RSP);
496 newThread->SavedState.RIP = rip;
498 // Lock list and add to active
499 Threads_AddActive(newThread);
501 return newThread->TID;
505 * \fn int Proc_SpawnWorker(void)
506 * \brief Spawns a new worker thread
508 int Proc_SpawnWorker(void (*Fcn)(void*), void *Data)
511 Uint stack_contents[4];
513 cur = Proc_GetCurThread();
516 new = malloc( sizeof(tThread) );
518 Warning("Proc_SpawnWorker - Out of heap space!\n");
521 memcpy(new, &gThreadZero, sizeof(tThread));
523 new->TID = giNextTID++;
525 // Create the stack contents
526 stack_contents[3] = (Uint)Data;
527 stack_contents[2] = 1;
528 stack_contents[1] = (Uint)Fcn;
529 stack_contents[0] = (Uint)new;
531 // Create a new worker stack (in PID0's address space)
532 // The stack is relocated by this code
533 new->KernelStack = MM_NewWorkerStack(stack_contents, sizeof(stack_contents));
535 new->SavedState.RSP = new->KernelStack - sizeof(stack_contents);
536 new->SavedState.RIP = (Uint)&NewTaskHeader;
538 Log("New (Worker) %p, rsp = %p\n", new->SavedState.RIP, new->SavedState.RSP);
541 new->Status = THREAD_STAT_PREINIT;
542 Threads_AddActive( new );
548 * \fn Uint Proc_MakeUserStack(void)
549 * \brief Creates a new user stack
551 Uint Proc_MakeUserStack(void)
554 Uint base = USER_STACK_TOP - USER_STACK_SZ;
556 // Check Prospective Space
557 for( i = USER_STACK_SZ >> 12; i--; )
558 if( MM_GetPhysAddr( base + (i<<12) ) != 0 )
561 if(i != -1) return 0;
563 // Allocate Stack - Allocate incrementally to clean up MM_Dump output
564 for( i = 0; i < USER_STACK_SZ/0x1000; i++ )
566 if( !MM_Allocate( base + (i<<12) ) )
569 Log_Error("Proc", "Unable to allocate user stack (%i pages requested)", USER_STACK_SZ/0x1000);
571 MM_Deallocate( base + (i<<12) );
576 return base + USER_STACK_SZ;
581 * \fn void Proc_StartUser(Uint Entrypoint, Uint *Bases, int ArgC, char **ArgV, char **EnvP, int DataSize)
582 * \brief Starts a user task
584 void Proc_StartUser(Uint Entrypoint, Uint *Bases, int ArgC, char **ArgV, char **EnvP, int DataSize)
586 Uint *stack = (void*)Proc_MakeUserStack();
591 LOG("stack = 0x%x", stack);
594 stack = (void*)( (Uint)stack - DataSize );
595 memcpy( stack, ArgV, DataSize );
597 // Adjust Arguments and environment
598 delta = (Uint)stack - (Uint)ArgV;
599 ArgV = (char**)stack;
600 for( i = 0; ArgV[i]; i++ ) ArgV[i] += delta;
603 for( i = 0; EnvP[i]; i++ ) EnvP[i] += delta;
605 // User Mode Segments
606 ss = 0x23; cs = 0x1B;
609 *--stack = (Uint)EnvP;
610 *--stack = (Uint)ArgV;
611 *--stack = (Uint)ArgC;
614 *--stack = 0; // Return Address
616 Proc_StartProcess(ss, (Uint)stack, 0x202, cs, Entrypoint);
619 void Proc_StartProcess(Uint16 SS, Uint Stack, Uint Flags, Uint16 CS, Uint IP)
621 if( CS != 0x1B || SS != 0x23 ) {
622 Log_Error("Proc", "Proc_StartProcess: CS / SS are not valid (%x, %x)",
627 __asm__ __volatile__ (
628 "mov %0, %%rsp;\n\t" // Set stack pointer
629 "mov %1, %%r11;\n\t" // Set stack pointer
631 : : "r" (Stack), "c" (IP), "r" (Flags)
638 * \fn int Proc_Demote(Uint *Err, int Dest, tRegs *Regs)
639 * \brief Demotes a process to a lower permission level
640 * \param Err Pointer to user's errno
641 * \param Dest New Permission Level
642 * \param Regs Pointer to user's register structure
644 int Proc_Demote(Uint *Err, int Dest, tRegs *Regs)
646 int cpl = Regs->CS & 3;
648 if(Dest > 3 || Dest < 0) {
659 // Change the Segment Registers
660 Regs->CS = (((Dest+1)<<4) | Dest) - 8;
661 Regs->SS = ((Dest+1)<<4) | Dest;
667 * \brief Calls a signal handler in user mode
668 * \note Used for signals
670 void Proc_CallFaultHandler(tThread *Thread)
672 // Rewinds the stack and calls the user function
674 __asm__ __volatile__ ("mov %0, %%rbp;\n\tcall Proc_ReturnToUser" :: "r"(Thread->FaultHandler));
678 void Proc_DumpThreadCPUState(tThread *Thread)
680 Log(" At %04x:%016llx", Thread->SavedState.UserCS, Thread->SavedState.UserRIP);
684 * \fn void Proc_Scheduler(int CPU)
685 * \brief Swap current thread and clears dead threads
687 void Proc_Scheduler(int CPU, Uint RSP, Uint RIP)
692 Time_UpdateTimestamp();
694 // If the spinlock is set, let it complete
695 if(IS_LOCKED(&glThreadListLock)) return;
697 // Get current thread
698 thread = gaCPUs[CPU].Current;
703 // Reduce remaining quantum and continue timeslice if non-zero
704 if(thread->Remaining--) return;
705 // Reset quantum for next call
706 thread->Remaining = thread->Quantum;
708 // Save machine state
709 thread->SavedState.RSP = RSP;
710 thread->SavedState.RIP = RIP;
712 // LogF("\nSaved %i, RIP = %p, rsp = %p\n", thread->TID, thread->SavedState.RIP, thread->SavedState.RSP);
714 // TODO: Make this more stable somehow
716 regs = (tRegs*)(RSP+(1)*8); // CurThread
717 thread->SavedState.UserCS = regs->CS;
718 thread->SavedState.UserRIP = regs->RIP;
724 tThread *oldthread = thread;
728 thread = Threads_GetNextToRun(CPU, thread);
732 thread = gaCPUs[CPU].IdleThread;
733 //Warning("Hmm... Threads_GetNextToRun returned NULL, I don't think this should happen.\n");
737 if(thread == NULL ) {
741 if( thread != oldthread ) {
747 #if DEBUG_TRACE_SWITCH
748 LogF("\nSwitching to task %i, CR3 = 0x%x, RIP = %p, RSP = %p\n",
750 thread->MemState.CR3,
751 thread->SavedState.RIP,
752 thread->SavedState.RSP
758 LogF("CPU = %i", CPU);
759 // Set current thread
760 gaCPUs[CPU].Current = thread;
762 // Update Kernel Stack pointer
763 gTSSs[CPU].RSP0 = thread->KernelStack-4;
766 __asm__ __volatile__ (
768 "mov %0, %%rsp\n\t" // Restore RSP
770 "invlpg 0x1000(%%rsp)\n\t"
771 "invlpg -0x1000(%%rsp)\n\t"
772 "jmp *%1" : : // And return to where we saved state (Proc_Clone or Proc_Scheduler)
773 "r"(thread->SavedState.RSP), "r"(thread->SavedState.RIP),
774 "r"(thread->MemState.CR3), "a" (0)
776 for(;;); // Shouldn't reach here
780 EXPORT(Proc_SpawnWorker);